Officials warn that threats to take a handful of governments which have signed 'open skies' agreements with the US to the European Court of Justice for alleged breaches of the Union treaty could be revived if the Commission's ambitions to negotiate a global aviation agreement with the US continue to be blocked. "We would not have embarked on the [legal] procedure if we had not believed Community interests were seriously affected," said one.

The warning comes as concern grows within the Commission that it may be running out of time to convince EU governments that they would get more by negotiating collectively with the US than going it alone with what it argues are unbalanced bilateral deals.

Spain, France and Italy are among the large Union member states which have not yet signed such deals with the US. As long as that remains the case, the Commission still has some negotiating leverage with Washington for a wider European agreement.

But there are fears that these countries are moving fast towards sealing their own open skies accords as their main state airlines - Iberia, Air France and Alitalia - look to create the kind of close transatlantic partnerships already completed by most of their rivals.

The Netherlands, Sweden, Germany, Belgium, Finland, Luxembourg, Denmark and Austria have already secured open skies deals with the US. The Commission claims they breached treaty rules by concluding trade agreements with an EU-wide impact.

Legal action was frozen when governments agreed last year to a complicated two-stage mandate for talks between Union officials and their transatlantic counterparts. However, many governments continue to be wary of giving the Commission a greater say. "I think countries that have said 'no' in the past will continue to say 'no'," said one national official ahead of the meeting.

Transport Commissioner Neil Kinnock hopes a mixture of carrots and sticks will win ministers over. Governments will be asked to explain their concerns, with Kinnock stressing that individual member states would be brought on board to take part in any negotiations with the US.